3, 4, 5, 6-tetrahydrothiophthalide



United States Patent 3,335,153 3,4,5,G-TETRAHYDROTHIOPHTHALIDE Robert W.Campbell, Orinda, Califi, assignor to Chevron Research Company, acorporation of Delaware No Drawing. Filed Oct. 20, 1964, Ser. No.405,238 2 Claims. (Cl. 260332.3)

This invention relates to the novel composition, 3,4,5,6-tetrahydrothiophthalide (THTP) The subject compound is a reactivechemical intermediate useful for the preparation in particular of dyesand chlorinated organic sulfur containing insecticides. Under mildoxidative coupling conditions two molecules of the subject compounddimerizes yielding the chromophoric compound:

The novel compound may be prepared by the reduction ofcyclohexane-1,2-dicarboxylic anhydride using hydrogen and hydrogensulfide under pressure in a steel-lined autoclave.

Example 1 3,335,153 Patented Aug. 8, 1967 sodium bicarbonate and thenevaporated and cooled to 0% C. The oil partially crystallized. A stickyyellow solid was collected. A carbon decolorization and two subsequentrecrystallizations from methanol yielded a white crystalline product,M.P. 42-43" C.; )t in 95% ethanol: 233 III/L (log (4.02), 258 inflection(3.43); V 1690, V =0 1655 cm. in carbon tetrachloride. The nuclearmagnetic resonance spectrum (Varian A- spectrometer) showed followingabsorptions (in tau-values, tetramethylsilane external standard): 8.25,quartet, unconjugated methylene; 7.70, diffuse multiplet, vinylmethylene; 6.17, singlet, split slightly, vinyl methylene adjacent tosulfur; calculated area ratio 2:2:1; observed 2.1:2.1:1.

Analysia-Calculated for C H OS (154.31); C, 62.26; H, 6.53; S, 20.68.Found: C, 61.98; H, 6.48; S, 20.52. The molecular weight (mass spectra)was found to be 154.

Example 2 12 g. of THTP were dissolved in 250 ml. of chloroform and themixture cooled and maintained at about 0 C. Chlorine gas was passed overthe solution surface until an estimated 2 moles of chlorine per mol ofTHTP had reacted. Hydrogen chloride was evolved as a by-product. Thestructure of the resulting product was shown by Nuclear MagneticResonance spectra to correspond to 7,7-dichloro-3,4,5,6-tetrahydrothiophthalide. There was a multiplet at 1.9(tau-values), 2.5 and 2.9 ppm. in a ratio of 2:1:1. The compound is areactive polyfunctional chemical intermediate as well as havinginsecticidal characteristics.

I claim:

1. 3,4,5,G-tetrahydrothiophthalide.

2. 7,7-dichloro-3,4,5,G-tetrahydrothiophth-alide.

References Cited UNITED STATES PATENTS 3,061,612 10/1962 Toland 260330.5

WALTER A. MODANCE, Primary Examiner. JOHN 'D. RANDOLPH, Examiner.

C. SHURKO, Assistant Examiner.

1. 3,4,5,6-TETRAHYDROTHIOPHTHALIDE.